The results show that thermal delousing significantly reduces the number of mobile and adult lice.
The treatment also had no negative impact on fish welfare. There were no significant acute injuries observed on the fish, the fish ate well after a few days and the mortality rate was low.
Effect on lice
Estimated reduction of motile lice varied from about 75 and up to 100 per cent by thermal delousing.
No statistically clear effect was seen in sessile lice localities included in the project. There was, however, a registered decline in the number of sessile lice after the treatment.
Several localities had the same level of lice three weeks after treatment before delousing.
This was probably due to infection from neighbors and their own cages into the further development of lice on the locality, and the development of any survivors sessile lice after treatment.
Need for non-drug sea lice treatment
Developing non-drug methods for the treatment of sea lice is very important for a sustainable industry.
The biggest challenges during this project were related to penetration and pump system.
Alteration of the pump system and other improvements at the machine has improved the performance from start to finish of the project.
